Thanks for the report! Still waiting for some localization strings before I'll upload the next version. In the meantime, you could fix that yourself by  changing 
  script.on_event(defines.events[event], function (event)
to
  script.on_event(defines.events[event], function (event)
    if not game.players[event.player_index].character then 
      return 
    end
This should be line 580. Please not that the mod won't track what you have in your inventory when you're in Editor or God mode. So, if you should decide to change to a character later on, you'll start with an empty inventory. I may add God-mode compatibility in the future (not sure if that really would be a good idea), but for now the current fix should  still be better than a crash. :-)